FIR Digital Filter Design and Realization by Using MATLAB
Abstract
In this thesis, I will discuss the approximation schemes for digital filter with finite impulse response (FIR) and I will present the methods for determining the multiplier coefficients and the filter order, in such a way that the resulting frequency response satisfies a set of prescribed specifications.
In some case, FIR filters are considered inefficient in the sense that they require a high-order transfer function to satisfy the system requirements when compared to the order required by digital filters with infinite impulse response. However, FIR digital filters do possess a few implementation advantages such as a possible exact linear-phase characteristic and intrinsically stable implementations, when using no recursive realizations. In addition, the computational complexity of FIR digital filters can be reduced if they are implemented using fast numerical algorithms such as the fast Fourier transform.
I start by discussing the ideal frequency response characteristics commonly used by FIR filters, as well as their corresponding impulse responses. I include in the discussing low pass, high pass and band pass filters.
I go on to discuss the frequency sampling and the window methods for approximating FIR digital filters, focusing on the rectangular, triangular, Henning, Hamming, Blackman and Kaiser windows. At the same time, I conclude the thesis by discussing the use of MATLAB for designing FIR filters.
At last, all methods are analyzed.
Key words: FIR Digital Filter ;Window methods;The frequency responds